When complete, place stocking cap over kit and carry in passenger
compartment of car. If you have a 3-pound can, you will still have additional
room for band-aids, aspirin, small radio, etc. If there is still room left,
increase the quantity of any of the above items or improvise items you feel
might be necessary.

Other items you may want to keep in the vehicle:

Large
plastic garbage bag.

Pencil
stub and paper.

Plastic
whistle.

You may want to keep the survival kit in the passenger compartment in case
you go into a ditch and can't get to or open the trunk.

(Information
re-printed from the Wisconsin Department of Transportation Website)